Search results for: Distributed renewable energy resource
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4239

Search results for: Distributed renewable energy resource

1239 Exponential Stability of Linear Systems under a Class of Unbounded Perturbations

Authors: Safae El Alaoui, Mohamed Ouzahra

Abstract:

In this work, we investigate the exponential stability of a linear system described by x˙ (t) = Ax(t) − ρBx(t). Here, A generates a semigroup S(t) on a Hilbert space, the operator B is supposed to be of Desch-Schappacher type, which makes the investigation more interesting in many applications. The case of Miyadera-Voigt perturbations is also considered. Sufficient conditions are formulated in terms of admissibility and observability inequalities and the approach is based on some energy estimates. Finally, the obtained results are applied to prove the uniform exponential stabilization of bilinear partial differential equations.

Keywords: Exponential stabilization, unbounded operator, Desch-Schappacher, Miyadera-Voigt operator.

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1238 Discontinuous Galerkin Method for Total Variation Minimization on Inpainting Problem

Authors: Xijian Wang

Abstract:

This paper is concerned with the numerical minimization of energy functionals in BV ( ) (the space of bounded variation functions) involving total variation for gray-scale 1-dimensional inpainting problem. Applications are shown by finite element method and discontinuous Galerkin method for total variation minimization. We include the numerical examples which show the different recovery image by these two methods.

Keywords: finite element method, discontinuous Galerkin method, total variation minimization, inpainting

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1237 Enhancement of a 3D Sound Using Psychoacoustics

Authors: Kyosik Koo, Hyungtai Cha

Abstract:

Generally, in order to create 3D sound using binaural systems, we use head related transfer functions (HRTF) including the information of sounds which is arrived to our ears. But it can decline some three-dimensional effects in the area of a cone of confusion between front and back directions, because of the characteristics of HRTF. In this paper, we propose a new method to use psychoacoustics theory that reduces the confusion of sound image localization. In the method, HRTF spectrum characteristic is enhanced by using the energy ratio of the bark band. Informal listening tests show that the proposed method improves the front-back sound localization characteristics much better than the conventional methods

Keywords: HRTF, 3D sound, Psychoacoustics, Localization

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1236 Artificial Intelligent in Optimization of Steel Moment Frame Structures: A Review

Authors: Mohsen Soori, Fooad Karimi Ghaleh Jough

Abstract:

The integration of Artificial Intelligence (AI) techniques in the optimization of steel moment frame structures represents a transformative approach to enhance the design, analysis, and performance of these critical engineering systems. The review encompasses a wide spectrum of AI methods, including machine learning algorithms, evolutionary algorithms, neural networks, and optimization techniques, applied to address various challenges in the field. The synthesis of research findings highlights the interdisciplinary nature of AI applications in structural engineering, emphasizing the synergy between domain expertise and advanced computational methodologies. This synthesis aims to serve as a valuable resource for researchers, practitioners, and policymakers seeking a comprehensive understanding of the state-of-the-art in AI-driven optimization for steel moment frame structures. The paper commences with an overview of the fundamental principles governing steel moment frame structures and identifies the key optimization objectives, such as efficiency of structures. Subsequently, it delves into the application of AI in the conceptual design phase, where algorithms aid in generating innovative structural configurations and optimizing material utilization. The review also explores the use of AI for real-time structural health monitoring and predictive maintenance, contributing to the long-term sustainability and reliability of steel moment frame structures. Furthermore, the paper investigates how AI-driven algorithms facilitate the calibration of structural models, enabling accurate prediction of dynamic responses and seismic performance. Thus, by reviewing and analyzing the recent achievements in applications artificial intelligent in optimization of steel moment frame structures, the process of designing, analysis, and performance of the structures can be analyzed and modified.

Keywords: Artificial Intelligent, optimization process, steel moment frame, structural engineering.

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1235 Strong Adhesion and High Wettability at Polyetheretherketone-Resin/Titanium-Dioxide Interface Obtained with Crystal-Orientation Control

Authors: Tomio Iwasaki, Yosuke Kawahito

Abstract:

The adhesion strength and wettability at the interfaces between a polyetheretherketone (PEEK) resin and titanium dioxide (TiO2) have become more important because direct joining of PEEK resin and titanium (Ti), whose surface has usually the oxide (TiO2), is needed not only in vehicles such as airplanes, automobiles, and space vehicles, but also in medical devices such as implants. To realize strong joint between the PEEK resin and TiO2, the dependence of the adhesion strength and wettability on crystal orientations of rutile TiO2 were investigated by using molecular simulations. Molecular dynamics simulations were conducted by combining quantum-mechanics equation of electrons with Newton’s equation of motion of nuclear coordinates (atomic coordinates). By putting a PEEK-resin sphere on a rutile TiO2 surface and by heating the system to 650 K, the contact angles at the interfaces were calculated to evaluate the wettability. After the system is cooled to 300 K from 650 K, to evaluate the adhesin strength, the adhesive fracture energy is calculated as the difference between the energy of the PEEK-TiO2 attached state and that of the PEEK-TiO2 detached state. The results of the contact angles showed that PEEK resin on the TiO2(100) and that on the TiO2(001) surface has low wettability with large contact angles. On the other hand, PEEK resin on the TiO2(110) surface has high wettability with a small contact angle. The results of the adhesive fracture energies showed that the adhesion at the PEEK-resin/TiO2(100) and PEEK-resin/TiO2(001) interfaces are weak. On the other hand, the adhesion at the PEEK-resin/TiO2(110) interface is strong. To clarify the reason that the higher wettability and stronger adhesion are obtained at the PEEK/TiO2(110) interface than at the at the PEEK/TiO2(100) and PEEK/TiO2(001) interfaces, atomic configurations at the interfaces were visualized. The atomic configuration at the PEEK/TiO2(110) interface showed that the lattice-matched coherent interface is realized, and the atomic density is high. On the other hand, the atomic configuration at the PEEK/TiO2(001) interface showed the lattice-unmatched incoherent interface. The atomic configuration at the PEEK/TiO2(100) interface showed that the atomic density is very low although the lattice-matched interface is realized. Therefore, the lattice matching and the high atomic density at the PEEK/TiO2(001) interface are considered to be dominant factors in the high wettability and strong adhesion.

Keywords: Adhesion, direct joining, PEEK, TiO2, wettability.

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1234 Authentic Learning for Computer Network with Mobile Device-Based Hands-On Labware

Authors: Kai Qian, Ming Yang, Minzhe Guo, Prabir Bhattacharya, Lixin Tao

Abstract:

Computer network courses are essential parts of college computer science curriculum and hands-on networking experience is well recognized as an effective approach to help students understand better about the network concepts, the layered architecture of network protocols, and the dynamics of the networks. However, existing networking labs are usually server-based and relatively cumbersome, which require a certain level of specialty and resource to set up and maintain the lab environment. Many universities/colleges lack the resources and build-ups in this field and have difficulty to provide students with hands-on practice labs. A new affordable and easily-adoptable approach to networking labs is desirable to enhance network teaching and learning. In addition, current network labs are short on providing hands-on practice for modern wireless and mobile network learning. With the prevalence of smart mobile devices, wireless and mobile network are permeating into various aspects of our information society. The emerging and modern mobile technology provides computer science students with more authentic learning experience opportunities especially in network learning. A mobile device based hands-on labware can provide an excellent ‘real world’ authentic learning environment for computer network especially for wireless network study. In this paper, we present our mobile device-based hands-on labware (series of lab module) for computer network learning which is guided by authentic learning principles to immerse students in a real world relevant learning environment. We have been using this labware in teaching computer network, mobile security, and wireless network classes. The student feedback shows that students can learn more when they have hands-on authentic learning experience. 

Keywords: Mobile computing, android, network, labware.

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1233 Production Structures of Energy Based on Water Force, Its Infrastructure Protection, and Possible Causes of Failure

Authors: Gabriela-Andreea Despescu, Mădălina-Elena Mavrodin, Gheorghe Lăzăroiu, Florin Adrian Grădinaru

Abstract:

The purpose of this paper is to contribute to the enhancement of a hydroelectric plant protection by coordinating protection measures / existing security and introducing new measures under a risk management process. In addition, plan identifies key critical elements of a hydroelectric plant, from its level vulnerabilities and threats it is subjected to in order to achieve the necessary protection measures to reduce the level of risk.

Keywords: Critical infrastructure, risk analysis, critical infrastructure protection, vulnerability, risk management, turbine, Impact analysis.

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1232 Ingenious Eco-Technology for Transforming Food and Tanneries Waste into a Soil Bio-Conditioner and Fertilizer Product Used for Recovery and Enhancement of the Productive Capacity of the Soil

Authors: Petre Voicu, Mircea Oaida, Radu Vasiu, Catalin Gheorghiu, Aurel Dumitru

Abstract:

The present work deals with the way in which food and tobacco waste can be used in agriculture. As a result of the lack of efficient technologies for their recycling, we are currently faced with the appearance of appreciable quantities of residual organic residues that find their use only very rarely and only after long storage in landfills. The main disadvantages of long storage of organic waste are the unpleasant smell, the high content of pathogenic agents, and the high content in the water. The release of these enormous amounts imperatively demands the finding of solutions to ensure the avoidance of environmental pollution. The measure practiced by us and presented in this paper consists of the processing of this waste in special installations, testing in pilot experimental perimeters, and later administration on agricultural lands without harming the quality of the soil, agricultural crops, and the environment. The current crisis of raw materials and energy also raises special problems in the field of organic waste valorization, an activity that takes place with low energy consumption. At the same time, their composition recommends them as useful secondary sources in agriculture. The transformation of food scraps and other residues concentrated organics thus acquires a new orientation, in which these materials are seen as important secondary resources. The utilization of food and tobacco waste in agriculture is also stimulated by the increasing lack of chemical fertilizers and the continuous increase in their price, under the conditions that the soil requires increased amounts of fertilizers in order to obtain high, stable, and profitable production. The need to maintain and increase the humus content of the soil is also taken into account, as an essential factor of its fertility, as a source and reserve of nutrients and microelements, as an important factor in increasing the buffering capacity of the soil, and the more reserved use of chemical fertilizers, improving the structure and permeability for water with positive effects on the quality of agricultural works and preventing the excess and/or deficit of moisture in the soil.

Keywords: Organic residue, food and tannery waste, fertilizer, soil.

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1231 Vehicle Aerodynamics: Drag Reduction by Surface Dimples

Authors: C. K. Chear, S. S. Dol

Abstract:

For a bluff body, dimples behave like roughness elements in stimulating a turbulent boundary layer, leading to delayed flow separation, a smaller wake and lower form drag. This is very different in principle from the application of dimples to streamlined body, where any reduction in drag would be predominantly due to a reduction in skin friction. In the present work, a car model with different dimple geometry is simulated using k-ε turbulence modeling to determine its effect to the aerodynamics performance. Overall, the results show that the application of dimples manages to reduce the drag coefficient of the car model.

Keywords: Aerodynamics, Boundary Layer, Dimple, Drag, Kinetic Energy, Turbulence.

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1230 Access of Small and Medium Enterprises to Finance in Rural Areas: Case of Indonesia and Thailand

Authors: N. Ikasari, T. Sumransat, U. Eko, R. Kusumastuti

Abstract:

Small and medium enterprises (SMEs) are regarded as the engine for economic development, notwithstanding their continuous financing conundrum. In the case of developing countries, access to finance is a reflection of the effectiveness of government policy. The widely accepted perspective to assess small businesses’ access to finance is that of economic view. The existing body of literature presents access to finance in three dimensions; they are accessibility, eligibility and affordability. Within this perspective, the role of socio-cultural has not explored. This study is aimed at investigating the existence of any socio-cultural factors within access to finance issue in Asian countries where governance is enriched by countries’ values and beliefs. The significance of this study is the instigation of supplementary dimension to assess access to finance that eventually contributes to the development of micro-finance policy. Indonesia and Thailand are selected as cases in point, where distinction is drawn on the level of cultural diversity and micro-finance policy in respective country. A questionnaire is used to collect information related to the three dimensions of access to finance as well as to explore alternative financing reasoning to elaborate the issue from the demand side. Questionnaires are distributed to 60 small business owners operating in Indonesia and the same number in Thailand. In order to present a complete understanding on the matter at hand, interviews with banks are conducted to capture the perspective as presented by the supply side. Research findings show that small business owners and banks in Indonesia and Thailand are in agreement that access to finance is not deemed as an issue. However, trust issue that exists mutually between financing users and providers leads small business owners in Indonesia to look for alternative financing other than banks. The findings contribute to the refinement of micro-financing policy in Indonesia and Thailand.

Keywords: Access to finance, Indonesia, small and medium enterprises, Thailand.

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1229 Pinch Analysis of Triple Pressure Reheat Supercritical Combined Cycle Power Plant

Authors: Sui Yan Wong, Keat Ping Yeoh, Chi Wai Hui

Abstract:

In this study, supercritical steam is introduced to Combined Cycle Power Plant (CCPP) in an attempt to further optimize energy recovery. Subcritical steam is commonly used in the CCPP, operating at maximum pressures around 150-160 bar. Supercritical steam is an alternative to increase heat recovery during vaporization period of water. The idea of improvement using supercritical steam is further examined with the use of exergy, pinch analysis and Aspen Plus simulation.

Keywords: Exergy, pinch, combined cycle power plant, CCPP, supercritical steam.

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1228 A Mobile Agent-based Clustering Data Fusion Algorithm in WSN

Authors: Xiangbin Zhu, Wenjuan Zhang

Abstract:

In wireless sensor networks,the mobile agent technology is used in data fusion. According to the node residual energy and the results of partial integration,we design the node clustering algorithm. Optimization of mobile agent in the routing within the cluster strategy for wireless sensor networks to further reduce the amount of data transfer. Through the experiments, using mobile agents in the integration process within the cluster can be reduced the path loss in some extent.

Keywords: wireless sensor networks, data fusion, mobile agent

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1227 Study of Current Sheath Velocities in Tridimensional with Sahand Plasma Focus

Authors: M.A. Mohammadi, H.Alinejad, A.Piri

Abstract:

The current sheath dynamics in plasma focus facilities is the most important factors. In this paper the current sheath velocity at three dimensional with Sahand plasma focus facility is investigated. For this purpose the discharge is produced in argon gas with deposited energy lying in the range of 20-37kJ. The current sheath is monitored using two tridimensional magnetic probes. These probes installed near the surface of the interior electrode (anode) at 125mm from the anode axis (pinch place). The effect of gas pressure on the current sheath velocity also is investigated.

Keywords: Plasma focus, Current sheath, magnetic probe

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1226 EnArgus: A Knowledge-Based Search Application for Energy Research Projects

Authors: Frederike Ohrem, Lukas Sikorski, Bastian Haarmann

Abstract:

Often the users of a semantic search application are facing the problem that they do not find appropriate terms for their search. This holds especially if the data to be searched is from a technical field in which the user does not have expertise. In order to support the user finding the results he seeks, we developed a domain-specific ontology and implemented it into a search application. The ontology serves as a knowledge base, suggesting technical terms to the user which he can add to his query. In this paper, we present the search application and the underlying ontology as well as the project EnArgus in which the application was developed.

Keywords: Information system, knowledge representation, ontology, semantic search.

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1225 Fabrication of Al/Cu Clad Sheet by Shear Extrusion

Authors: Joon Ho Kim, Duck Su Kim, Tae Kwon Ha

Abstract:

Aluminum/Copper clad sheet has been fabricated using asymmetric extrusion method, which caused severe shear deformation between Al and Cu plate to easily bond to each other. Interfacial microstructure and mechanical properties of Al/Cu clad were studied by scanning electron microscope equipped with energy dispersive X-ray detector, micro-hardness, and tension tests. The asymmetric extrusion bonding was very effective to provide a good interface for atoms diffusion during subsequent annealing. The strength of bonding was higher with the increasing extrusion ratio.

Keywords: Aluminum/Copper clad sheet, Asymmetric extrusion, Interfacial microstructure, Annealing, Tensile test.

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1224 The Effect of Natural Light on the Performance of Visible Light Communication Systems

Authors: Mahmoud Beshr, Ivan Andonovic, Moustafa H. Aly

Abstract:

Visible Light Communication (VLC) offers advantages of low energy consumption, licence free and RF interference free operation. One application area for VLC is in the provision of health centred services circumventing issues of interference with any biomedical device within the environment. VLC performamce is affected by natural light restricting systems avilability and relibility. The paper presents an analysis of the performance of VLC systems under different meteorological conditions. The evaluation considered the impact of natural light as a function of different reflection surfaces in different room sizes.

Keywords: Visible light communication, impulse reponse , performance analysis , natural light.

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1223 Manufacture of Electroless Nickel/YSZ Composite Coatings

Authors: N. Bahiyah Baba, W. Waugh, A.M. Davidson

Abstract:

The paper discusses optimising work on a method of processing ceramic / metal composite coatings for various applications and is based on preliminary work on processing anodes for solid oxide fuel cells (SOFCs). The composite coating is manufactured by the electroless co-deposition of nickel and yttria stabilised zirconia (YSZ) simultaneously on to a ceramic substrate. The effect on coating characteristics of substrate surface treatments and electroless nickel bath parameters such as pH and agitation methods are also investigated. Characterisation of the resulting deposit by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) is also discussed.

Keywords: Electroless deposition, nickel, YSZ, composite

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1222 Optimal Synthesis of Multipass Heat Exchanger without Resorting to Correction Factor

Authors: Bharat B. Gulyani, Anuj Jain, Shalendra Kumar

Abstract:

Customarily, the LMTD correction factor, FT, is used to screen alternative designs for a heat exchanger. Designs with unacceptably low FT values are discarded. In this paper, authors have proposed a more fundamental criterion, based on feasibility of a multipass exchanger as the only criteria, followed by economic optimization. This criterion, coupled with asymptotic energy targets, provide the complete optimization space in a heat exchanger network (HEN), where cost-optimization of HEN can be performed with only Heat Recovery Approach temperature (HRAT) and number-of-shells as variables.

Keywords: heat exchanger, heat exchanger networks, LMTD correction factor, shell targeting.

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1221 Detailed Phenomenological Study of 14N Elastically Scattered on 12C in a wide Energy Range

Authors: Sh. Hamada, N. Burtebayev, N. Amangeldi, A. Amar

Abstract:

An experiment was performed with a 24.5 MeV 14N beam on a 12C target in the cyclotron DC-60 located in Astana, Kazakhstan, to study the elastic scattering of 14N on 12C; the scattering was also analyzed at different energies for tracking the phenomenon of remarkable structure at large angles. Its aims were to extend the measurements to very large angles, and attempt to uniquely identify the elastic scattering potential. Good agreement between the theoretical and experimental data has been obtained with suitable optical potential parameters. Optical model calculations with l -dependent imaginary potentials were also applied to the data and relatively good agreement was found.

Keywords: Optical Potential Codes, Elastic Scattering, SPIVALCode.

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1220 Exergy Analysis of a Cogeneration Plant

Authors: Derya Burcu Ozkan, Onur Kiziler, Duriye Bilge

Abstract:

Cogeneration may be defined as a system which contains electricity production and regain of the thermo value of exhaust gases simultaneously. The examination is based on the data-s of an active cogeneration plant. This study, it is aimed to determine which component of the system should be revised first to raise the efficiency and decrease the loss of exergy. For this purpose, second law analysis of thermodynamics is applied to each component due to consider the effects of environmental conditions and take the quality of energy into consideration as well as the quantity of it. The exergy balance equations are produced and exergy loss is calculated for each component. 44,44 % loss of exergy in heat exchanger, 29,59 % in combustion chamber, 18,68 % in steam boiler, 5,25 % in gas turbine and 2,03 % in compressor is calculated.

Keywords: Cogeneration, Exergy loss, Second law analysis

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1219 Friction Stir Welding Process: A Green Technology

Authors: Esther T. Akinlabi, Stephen A. Akinlabi

Abstract:

Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in the United Kingdom in 1991 for butt and lap welding of metals and plastics. This paper highlights the benefits of friction stir welding process as an energy efficient and a green technology process in the field of welding. Compared to the other conventional welding processes, its benefits, typical applications and its use in joining similar and dissimilar materials are also presented.

Keywords: Dissimilar materials, Friction Stir Welding, Green technology, similar materials.

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1218 The Effect of Chemical Treatment on TL Glow Curves of CdS/ZnS Thin Films Deposited by Vacuum Deposition Method

Authors: N. Dahbi, D-E. Arafah

Abstract:

The effect of chemical treatment in CdCl2 and thermal annealing in 400°C, on the defect structures of potentially useful ZnS\CdS solar cell thin films deposited onto quartz substrate and prepared by vacuum deposition method was studied using the Thermoluminesence (TL) techniques. A series of electron and hole traps are found in the various deposited samples studied. After annealing, however, it was observed that the intensity and activation energy of TL signal increases with loss of the low temperature electron traps.

Keywords: CdS, chemical treatment, heat treatment, Thermoluminescence, trapping parameters, thin film, vacuumdeposition, ZnS

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1217 Calculation of Wave Function at the Origin (WFO) for Heavy Mesons by Numerical Solving of the Schrodinger Equation

Authors: M. Momeni Feyli

Abstract:

Many recent high energy physics calculations involving charm and beauty invoke wave function at the origin (WFO) for the meson bound state. Uncertainties of charm and beauty quark masses and different models for potentials governing these bound states require a simple numerical algorithm for evaluation of the WFO's for these bound states. We present a simple algorithm for this propose which provides WFO's with high precision compared with similar ones already obtained in the literature.

Keywords: Mesons, Bound states, Schrodinger equation, Nonrelativistic quark model.

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1216 Reconsidering the Palaeo-Environmental Reconstruction of the Wet Zone of Sri Lanka: A Zooarchaeological Perspective

Authors: Kalangi Rodrigo, Kelum Manamendra-Arachchi

Abstract:

Bones, teeth, and shells have been acknowledged over the last two centuries as evidence of chronology, Palaeo-environment, and human activity. Faunal traces are valid evidence of past situations because they have properties that have not changed over long periods. Sri Lanka has been known as an Island, which has a diverse variety of prehistoric occupation among ecological zones. Defining the Paleoecology of the past societies has been an archaeological thought developed in the 1960s. It is mainly concerned with the reconstruction from available geological and biological evidence of past biota, populations, communities, landscapes, environments, and ecosystems. This early and persistent human fossil, technical, and cultural florescence, as well as a collection of well-preserved tropical-forest rock shelters with associated 'on-site ' Palaeoenvironmental records, makes Sri Lanka a central and unusual case study to determine the extent and strength of early human tropical forest encounters. Excavations carried out in prehistoric caves in the low country wet zone has shown that in the last 50,000 years, the temperature in the lowland rainforests has not exceeded 5 degrees. Based on Semnopithecus Priam (Gray Langur) remains unearthed from wet zone prehistoric caves, it has been argued periods of momentous climate changes during the Last Glacial Maximum (LGM) and Terminal Pleistocene/Early Holocene boundary, with a recognizable preference for semi-open ‘Intermediate’ rainforest or edges. Continuous genus Acavus and Oligospira occupation along with uninterrupted horizontal pervasive of Canarium sp. (‘kekuna’ nut) have proven that temperatures in the lowland rain forests have not changed by at least 5 °C over the last 50,000 years. Site catchment or territorial analysis cannot be any longer defensible, due to time-distance based factors as well as optimal foraging theory failed as a consequence of prehistoric people were aware of the decrease in cost-benefit ratio and located sites, and generally played out a settlement strategy that minimized the ratio of energy expended to energy produced.

Keywords: Palaeo-environment, palaeo-ecology, palaeo-climate, prehistory, zooarchaeology.

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1215 Starting Torque Study of Darrieus Wind Turbine

Authors: M. Douak, Z. Aouachria

Abstract:

The aim of our study is to project an optimized wind turbine of Darrieus type. This type of wind turbine is characterized by a low starting torque in comparison with the Savonius rotor allowing them to operate for a period greater than wind speed. This led us to reconsider the Darrieus rotor to optimize a design which will increase its starting torque. The study of a system of monitoring and control of the angle of attack of blade profile, which allows an auto start to wind speeds as low as possible is presented for the straight blade of Darrieus turbine. The study continues to extend to other configurations namely those of parabolic type.

Keywords: Darrieus turbine, pitch angle, self-stating, wind energy.

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1214 Quantum Computation using Two Component Bose-Einstein Condensates

Authors: Tim Byrnes

Abstract:

Quantum computation using qubits made of two component Bose-Einstein condensates (BECs) is analyzed. We construct a general framework for quantum algorithms to be executed using the collective states of the BECs. The use of BECs allows for an increase of energy scales via bosonic enhancement, resulting in two qubit gate operations that can be performed at a time reduced by a factor of N, where N is the number of bosons per qubit. We illustrate the scheme by an application to Deutsch-s and Grover-s algorithms, and discuss possible experimental implementations. Decoherence effects are analyzed under both general conditions and for the experimental implementation proposed.

Keywords: Quantum, computing, information, Bose-Einstein condensates, macroscopic.

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1213 The Effect of Agricultural Waste as a Filler in Fibre Cement Board Reinforced with Natural Cellulosic Fibres

Authors: Anuoluwapo S. Taiwo, David S. Ayre, Morteza Khorami, Sameer S. Rahatekar

Abstract:

This investigation aims to characterize the effect of corncob (CC), an agricultural waste, for potential use as a filler material, reducing cement in natural fibre-reinforced cement composite boards used for building applications in low-cost housing estates in developing countries. The CC is readily and abundantly available in many West African States. However, this agricultural waste product has not been put to any effective use. Hence, the objective of the current research is to convert this massive agro-waste resource into a potential material for use as filler materials reducing cement contents in fibre-cement board production. Kraft pulp fibre-reinforced cement composite boards were developed with the incorporation of the CC powder at varying percentages of 1-4% as filler materials to reduce the cement content, using a laboratory-simulated vacuum de-watering process. The mechanical properties of the developed cement boards were characterized through a three-point bending test, while the fractured morphology of the cement boards was examined through a Scanning Electron Microscope (SEM). Results revealed that the flexural strength of the composite board improved significantly with an optimum enhancement of 39% when compared to the reference sample without CC replacement, however, the flexural behaviour (ductility) of the composite board was slightly affected by the addition of the CC powder at higher percentage. SEM observation of the fractured surfaces revealed good bonding at the fibre-matrix interface as well as a ductile-to-brittle fracture mechanism. Overall, the composite board incorporated with 2% CC powder as filler materials had the optimum properties, satisfying the minimum requirements of relevant standards for fibre cement flat sheets.

Keywords: Kraft pulp fibre, fibre-cement board, agricultural waste, sustainability, building applications.

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1212 Effects of Four Dietary Oils on Cholesterol and Fatty Acid Composition of Egg Yolk in Layers

Authors: A. F. Agboola, B. R. O. Omidiwura, A. Oyeyemi, E. A. Iyayi, A. S. Adelani

Abstract:

Dietary cholesterol has elicited the most public interest as it relates with coronary heart disease. Thus, humans have been paying more attention to health, thereby reducing consumption of cholesterol enriched food. Egg is considered as one of the major sources of human dietary cholesterol. However, an alternative way to reduce the potential cholesterolemic effect of eggs is to modify the fatty acid composition of the yolk. The effect of palm oil (PO), soybean oil (SO), sesame seed oil (SSO) and fish oil (FO) supplementation in the diets of layers on egg yolk fatty acid, cholesterol, egg production and egg quality parameters were evaluated in a 42-day feeding trial. One hundred and five Isa Brown laying hens of 34 weeks of age were randomly distributed into seven groups of five replicates and three birds per replicate in a completely randomized design. Seven corn-soybean basal diets (BD) were formulated: BD+No oil (T1), BD+1.5% PO (T2), BD+1.5% SO (T3), BD+1.5% SSO (T4), BD+1.5% FO (T5), BD+0.75% SO+0.75% FO (T6) and BD+0.75% SSO+0.75% FO (T7). Five eggs were randomly sampled at day 42 from each replicate to assay for the cholesterol, fatty acid profile of egg yolk and egg quality assessment. Results showed that there were no significant (P>0.05) differences observed in production performance, egg cholesterol and egg quality parameters except for yolk height, albumen height, yolk index, egg shape index, haugh unit, and yolk colour. There were no significant differences (P>0.05) observed in total cholesterol, high density lipoprotein and low density lipoprotein levels of egg yolk across the treatments. However, diets had effect (P<0.05) on TAG (triacylglycerol) and VLDL (very low density lipoprotein) of the egg yolk. The highest TAG (603.78 mg/dl) and VLDL values (120.76 mg/dl) were recorded in eggs of hens on T4 (1.5% sesame seed oil) and was similar to those on T3 (1.5% soybean oil), T5 (1.5% fish oil) and T6 (0.75% soybean oil + 0.75% fish oil). However, results revealed a significant (P<0.05) variations on eggs’ summation of polyunsaturated fatty acid (PUFA). In conclusion, it is suggested that dietary oils could be included in layers’ diets to produce designer eggs low in cholesterol and high in PUFA especially omega-3 fatty acids.

Keywords: Dietary oils, Egg cholesterol, Egg fatty acid profile, Egg quality parameters.

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1211 Performance Monitoring of the Refrigeration System with Minimum Set of Sensors

Authors: Radek Fisera, Petr Stluka

Abstract:

This paper describes a methodology for remote performance monitoring of retail refrigeration systems. The proposed framework starts with monitoring of the whole refrigeration circuit which allows detecting deviations from expected behavior caused by various faults and degradations. The subsequent diagnostics methods drill down deeper in the equipment hierarchy to more specifically determine root causes. An important feature of the proposed concept is that it does not require any additional sensors, and thus, the performance monitoring solution can be deployed at a low installation cost. Moreover only a minimum of contextual information is required, which also substantially reduces time and cost of the deployment process.

Keywords: Condition monitoring, energy baselining, fault detection and diagnostics, commercial refrigeration.

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1210 Numerical Simulation of Electric and Hydrodynamic Fields Distribution in a Dielectric Liquids Electrofilter Cell

Authors: Narcis C. Ostahie, Tudor Sajin

Abstract:

In this paper a numerical simulation of electric and hydrodynamic fields distribution in an electrofilter for dielectric liquids cell is made. The simulation is made with the purpose to determine the trajectory of particles that moves under the action of external force in an electric and hydrodynamic field created inside of an electrofilter for dielectric liquids. Particle trajectory is analyzed for a dielectric liquid-solid particles suspension.

Keywords: Dielectric liquids, electrohydrodynamics, energy, high voltage, particles

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